Do internal emails make you more productive, or are they a big time-waster? Reports last week on the progress made by Atos — a Paris-based global information technology services company — in its efforts to prohibit internal emails have reignited the debate.

Few thought Atos CEO Thierry Breton would pull it off when he vowed last February to become a “zero-email company within three years.” After all, Atos is Europe’s largest IT services company with 78,500 employees across 42 countries. According to Breton, emails are a “pollution of the working environment.” Social media tools and online community networks would do the job just as well, he contended.

Last week, Atos claimed a 20% drop in the volume of its internal emails six months after Breton’s declaration, says a CNN report. Amid media flurry over the Atos move, The New York Times has featured it on its “Room for Debate” page.

The Case Against …

Email raises “efficiency concerns — like the amount of time spent using it — and is also is a less effective way of communicating,” says Wharton management professor Sigal Barsade, who specializes in emotional intelligence, among other areas. “Email can be dangerous, because it leads to miscommunication. We think we are saying one thing and think the other person understands it.” Indeed, Barsade preferred to give her comments in a phone interview rather than in an email.

Research shows that ambivalence is communicated primarily through facial expression and body language, to a lesser extent through vocal means, and only about 7% through the written word, says Barsade. “When you use email, by definition you are in a weakened position to really understand what the other person wants and how they will respond.” Also, with emails, people are more likely to “say or do things they would never do if the person was in front of them or on the phone,” she adds.

According to Wharton marketing professor Cassie Mogilner, who studies happiness as it relates to time and money, email can have a detrimental effect on productivity. “The frequent distractions [of emails] keep individuals from entering the highly creative, productive and generative state of being ‘in flow.’” That state is when an individual gets “completely engaged and absorbed in the task at hand, where time seems to melt away,” she says. Yet, she disagrees with the idea of banning emails, suggesting instead that individuals could take more responsibility for how they spend their time.

In addition to being “a constant distracter,” emails hurt productivity because many contain unimportant, useless and obsolete information, adds Maurice Schweitzer, Wharton professor of operations and information management. Furthermore, some emails contain harmful links that get past spam filters. “Worse, people often feel compelled to respond lest they risk offending others.”

Schweitzer contends that many people would do well to meet face-to-face, pick-up the phone or send a letter. “If issues are complicated or if emotions might run high, face-to-face meetings are the way to go,” he says. “Similarly, if confidentiality is important, email is a poor choice.” Face-to-face meetings are possible across the world with video chats, video conferencing and products like Skype, Mogilner adds.

The Case For …

Mogilner says the benefit of email is that it is a “very efficient form of communication because it allows people to convey information quickly to multiple people without having to synchronize the exchange.” It is helpful especially when all parties to a conversation cannot find a time that works for everyone, she adds.

Email’s big plus is it offers “a great vehicle for asynchronous communication,” according to Schweitzer. “I can send you a message now, and you can respond when you have time.” He describes it as “a fantastic vehicle” for reaching groups of people, plus it helps build a record or trail, is inexpensive and is great for sending documents, he adds.

Barsade acknowledges that emails help connect people and organizations in different geographic locations. “However, that’s not an excuse for avoiding phone calls or face-to-face conversations because we rely on these more immediate cues and thus, miscommunications are still going to be more likely to happen,” she says. “It could make companies less competitive.” In a globalized world, people still need to figure out new ways to communicate in real time, she adds. “Fundamentally, we are human beings, and the way that we most effectively and emotionally communicate is with body language, facial expressions and voice, none of which are in emails.”